Sensorless commutation of printed circuit brushless direct current motors

Article

Ahfock, A. and Gambetta, D.. 2010. "Sensorless commutation of printed circuit brushless direct current motors ." IET Electric Power Applications. 4 (6), pp. 397-406. https://doi.org/10.1049/iet-epa.2009.0133
Article Title

Sensorless commutation of printed circuit brushless direct current motors

ERA Journal ID4573
Article CategoryArticle
AuthorsAhfock, A. (Author) and Gambetta, D. (Author)
Journal TitleIET Electric Power Applications
Journal Citation4 (6), pp. 397-406
Number of Pages10
Year2010
Place of PublicationStevenage, Herts, UK
ISSN1350-2352
1751-8660
1751-8679
Digital Object Identifier (DOI)https://doi.org/10.1049/iet-epa.2009.0133
Abstract

The reliability and overall cost of brushless direct current (BLDC) motors can be significantly improved by implementation of an effective sensorless commutation control method. A recently proposed technique termed the 'equal inductance method' offers commutation control and starting performance equal to that obtained when using Hall sensors. However, the method applies to nominally symmetrical machines with high enough phase winding time constants. This study is about sensorless commutation of a class of motors which is characterised by significant asymmetry and relatively low-phase winding time constants. The motors in question are axial flux machines with ironless stators that may be wound or made up of printed circuits. The basic reason for the asymmetry is that the three-stator phases are stacked with each one of them located at a different axial distance from the rotor. The low-phase time constant is due to the ironless nature of the stator. The focus is on the printed circuit version of the motor. A new sensorless commutation technique has been developed, which is effectively a generalisation of the originally proposed equal inductance method. The theoretical basis behind the technique and practical results demonstrating its effectiveness are presented.

KeywordsBLDC motors; axial flux machines; equal inductance method; ironless stators; phase winding time constants; printed circuit brushless direct current motors; rotor; sensorless commutation control method
ANZSRC Field of Research 2020400907. Industrial electronics
400801. Circuits and systems
401706. Numerical modelling and mechanical characterisation
Public Notes

Copyright: The Institution of Engineering and Technology 2010.

Byline AffiliationsDepartment of Electrical, Electronic and Computer Engineering
Faculty of Engineering and Surveying
Institution of OriginUniversity of Southern Queensland
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